U.S. patent number 10,076,418 [Application Number 14/880,573] was granted by the patent office on 2018-09-18 for modular femoral provisional.
This patent grant is currently assigned to Zimmer, Inc.. The grantee listed for this patent is Zimmer, Inc.. Invention is credited to Travis H. Campbell, Brian D. Earl, Marvin Figueroa.
United States Patent |
10,076,418 |
Earl , et al. |
September 18, 2018 |
**Please see images for:
( Certificate of Correction ) ** |
Modular femoral provisional
Abstract
A provisional prosthetic system that replicates the
characteristics of a corresponding, nonprovisional femoral
prosthesis. The provisional prosthetic system may include a frame
component and a shell component. The frame component of the
provisional prosthetic system may be configured to be attached
directly to a resected femur. In one exemplary embodiment, the
frame component is impacted onto the resected femur to firmly seat
therewith. Once the frame component is secured to the resected
femur, a shell component of the provisional prosthetic system may
be positioned on and secured to the frame component. In one
exemplary embodiment, the frame component is made from a metallic
material. This allows for the frame component to maintain the
rigidity necessary to facilitate proper trialing. In another
exemplary embodiment, the shell component is a plastic.
Inventors: |
Earl; Brian D. (South Bend,
IN), Figueroa; Marvin (Warsaw, IN), Campbell; Travis
H. (Warsaw, IN) |
Applicant: |
Name |
City |
State |
Country |
Type |
Zimmer, Inc. |
Warsaw |
IN |
US |
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Assignee: |
Zimmer, Inc. (Warsaw,
IN)
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Family
ID: |
39733717 |
Appl.
No.: |
14/880,573 |
Filed: |
October 12, 2015 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20160030185 A1 |
Feb 4, 2016 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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11680711 |
Mar 1, 2007 |
9168155 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F
2/3859 (20130101); A61F 2/4684 (20130101); A61F
2002/30316 (20130101); A61F 2002/30614 (20130101); A61F
2002/30004 (20130101); A61F 2002/30026 (20130101); A61F
2220/0033 (20130101); A61F 2002/30352 (20130101); A61F
2002/30616 (20130101); A61F 2002/30329 (20130101); A61F
2002/30607 (20130101); A61F 2002/3863 (20130101); A61F
2220/0025 (20130101); A61F 2002/30014 (20130101); A61F
2002/30878 (20130101); A61F 2/38 (20130101); A61F
2002/30331 (20130101); A61F 2002/305 (20130101); A61F
2002/30354 (20130101); A61F 2002/30672 (20130101); A61F
2002/2825 (20130101); A61F 2002/30383 (20130101); A61F
2002/30604 (20130101) |
Current International
Class: |
A61F
2/38 (20060101); A61F 2/46 (20060101); A61F
2/30 (20060101); A61F 2/28 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2851156 |
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Aug 2004 |
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FR |
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WO-9730661 |
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Aug 1997 |
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WO |
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Other References
"U.S. Appl. No. 11/680,711, Advisory Action dated Apr. 2, 2015", 3
pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Examiner Interview Summary dated Jul.
2, 2015", 2 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Examiner Interview Summary dated Oct.
25, 2013", 3 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Examiner Interview Summary dated Oct.
30, 2009", 3 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Final Office Action dated Jan. 5,
2015", 14 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Final Office Action dated Jan. 22,
2014", 15 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Final Office Action dated Feb. 12,
2010", 5 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Non Final Office Action dated Jun. 24,
2013", 13 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Non Final Office Action dated Jul. 17,
2009", 4 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Non Final Office Action dated Sep. 12,
2014", 13 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Non Final Office Action dated Dec. 23,
2008", 7 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Notice of Allowance dated Jun. 25,
2015", 9 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Response filed Mar. 4, 2015 to Final
Office Action dated Jan. 5, 2015", 8 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Response filed Mar. 23, 2009 to Non
Final Office Action dated Dec. 23, 2008", 10 pgs. cited by
applicant .
"U.S. Appl. No. 11/680,711, Response filed May 5, 2015 to Final
Office Action dated Jan. 5, 2015", 8 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Response filed May 29, 2014 to Final
Office Action dated Jan. 22, 2014", 13 pgs. cited by applicant
.
"U.S. Appl. No. 11/680,711, Response filed Jun. 14, 2010 to Final
Office Action dated Feb. 12, 2010", 9 pgs. cited by applicant .
"U.S. Appl. No. 11/680,711, Response filed Sep. 24, 2013 to Non
Final Office Action dated Jun. 24, 2013", 14 pgs. cited by
applicant .
"U.S. Appl. No. 11/680,711, Response filed Nov. 5, 2009 to Non
Final Office Action dated Jul. 17, 2009", 7 pgs. cited by applicant
.
"U.S. Appl. No. 11/680,711, Response filed Dec. 8, 2014 to Non
Final Office Action dated Sep. 12, 2014", 12 pgs. cited by
applicant .
"Machine translation or FR 2851156 A1", Note: Cited in Sep. 2, 2014
Office Action by Examiner. Machine translation added to FR2851156A1
patent, (Sep. 2, 2014), 8 pgs. cited by applicant.
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Primary Examiner: Sharma; Yashita
Assistant Examiner: Preston; Rebecca
Attorney, Agent or Firm: Schwegman Lundberg & Woessner,
P.A.
Parent Case Text
CLAIM OF PRIORITY
This application is a continuation of U.S. patent application Ser.
No. 11/680,711, filed on Mar. 1, 2007, now issued as U.S. Pat. No.
9,168,155, the benefit of priority of which is claimed hereby, and
which is incorporated by reference herein in its entirety.
Claims
What is claimed is:
1. A modular provisional system comprising: a frame component
including: a first condylar base forming a first portion of a shell
contacting surface; a second condylar base forming a second portion
of the shell contacting surface, the second condylar base separated
from the first condylar base by a central gap; an anterior bridge
forming a third portion of the shell contacting surface and
connected on a lateral side to a first end of the first condylar
base and on a medial side to a first end of the second condylar
base; a posterior bridge forming a fourth portion of the shell
contacting surface and connected on a lateral side to a second end
of the first condylar base and on a medial side to a second end of
the second condylar base; a plurality of shell components, each of
said plurality of shell components configured to be releaseably
secured to the shell contacting surface of the frame component by a
plurality of engagement structures, the frame component and each of
said plurality of shell components cooperable to form different
provisional implants each of which replicate the characteristics of
at least one nonprovisional component of a prosthesis system,
wherein the plurality of engagement structures include a plurality
of projections from a frame contacting surface of the plurality of
shell components.
2. The modular provisional system of claim 1, wherein the posterior
bridge replicates the cam of a posterior stabilized implant.
3. The modular provisional system of claim 1, wherein the shell
contacting surface includes a plurality of openings corresponding
to the plurality of projections.
4. The modular provisional system of claim 3, wherein the anterior
bridge includes a first opening of the plurality of openings, the
first condylar base includes a second opening of the plurality of
openings, and the second condylar base includes a third opening of
the plurality of openings.
5. The modular provisional system of claim 1, wherein the first
condylar base includes a first post projecting from a first bone
contacting surface, and the second condylar base includes a second
post projecting from a second bone contacting surface.
6. The modular provisional system of claim 1, wherein the frame
component includes bone contacting surfaces configured to contact
the distal end of a resected femur on three separate planes formed
by resected surfaces including a distal resection, an anterior
resection and posterior resection.
7. The modular provisional system of claim 1, further comprising a
plurality of frame components; each of said plurality of frame
components configured to be secured to a distal end of a resected
femur.
8. A modular provisional system comprising: a frame component
including a bone contacting surface and a shell contacting surface,
the frame component comprising: a first condylar base forming a
first portion of the shell contacting surface; a second condylar
base forming a second portion of the shell contacting surface, the
second condylar base separated from the first condylar base by a
central gap; an anterior bridge connected on a lateral side to a
first end of the first condylar base and on a medial side to a
first end of the second condylar base; a posterior bridge, opposite
the anterior bridge, connecting a second end of the first condylar
base to a second end of the second condylar base; wherein the first
condylar base, the second condylar base, the anterior bridge, and
the posterior bridge form a portion of the shell contacting
surface; a plurality of shell components, each of said plurality of
shell components configured to be releaseably secured to the
support surface of the frame component by a plurality of engagement
structures, the frame component and each of said plurality of shell
components cooperable to form different provisional implants each
of which replicate the characteristics of at least one
nonprovisional component of a prosthesis system, wherein the
plurality of engagement structures include a plurality of
projections from a frame contacting surface of the plurality of
shell components.
9. The modular provisional system of claim 8, wherein the posterior
bridge replicates the cam of a posterior stabilized implant.
10. The modular provisional system of claim 8, wherein the shell
contacting surface includes a plurality of openings corresponding
to the plurality of projections.
11. The modular provisional system of claim 10, wherein the
anterior bridge includes a first opening of the plurality of
openings, the first condylar base includes a second opening of the
plurality of openings, and the second condylar base includes a
third opening of the plurality of openings.
12. The modular provisional system of claim 8, wherein the first
condylar base includes a first post projecting from a first bone
contacting surface, and the second condylar base includes a second
post projecting from a second bone contacting surface.
13. The modular provisional system of claim 8, wherein the bone
contacting surface of the frame component is configured to contact
the distal end of a resected femur on three separate planes formed
by resected surfaces including a distal resection, an anterior
resection and posterior resection.
14. A modular provisional system comprising: a plurality of frame
components, each of the plurality of frame components configured to
be secured to a distal end of a resected femur and including a bone
contacting surface and a shell contacting surface, each frame
component comprising: a first condylar base forming a first portion
of the shell contacting surface; a second condylar base forming a
second portion of the shell contacting surface, the second condylar
base separated from the first condylar base by a central gap; an
anterior bridge connected on a lateral side to a first end of the
first condylar base and on a medial side to a first end of the
second condylar base; a posterior bridge, opposite the anterior
bridge, connecting a second end of the first condylar base to a
second end of the second condylar base; wherein the first condylar
base, the second condylar base, the anterior bridge; and the
posterior bridge form a portion of the shell contacting surface; a
plurality of shell components, each of said plurality of shell
components configured to be releaseably secured to the support
surface of the frame component by a plurality of engagement
structures, the frame component and each of said plurality of shell
components cooperable to form different provisional implants each
of which replicate the characteristics of at least one
nonprovisional component of a prosthesis system.
Description
BACKGROUND
1. Field of the Invention
The present invention relates to a provisional prosthetic system
and the surgical methods for utilizing the same.
2. Description of the Related Art
Prostheses are commonly utilized to repair and/or replace damaged
bone and tissue in the human body. For example, a knee prosthesis
may be implanted to replace damaged or destroyed bone in the tibia
and/or femur and to recreate the natural, anatomical articulation
of the knee joint. To implant a prosthesis, orthopedic surgery is
performed which requires the creation of an incision in the skin of
the patient and may necessitate the retraction of surrounding
tissue to provide the surgeon with access to the surgical site.
To facilitate the implantation of a prosthesis, modular prostheses
may be utilized. Modular prostheses have several individual,
distinct components which are connected together to form the final,
implanted prosthesis. For example, a modular knee prosthesis may
include individual femoral, tibial, and patellar components which
are connected together to form the final, implanted knee
prosthesis. Additionally, one component, e.g., a femoral implant in
a modular knee prosthesis system, may be selected from several
different femoral components having various configurations, all of
which are included in the modular prosthesis system. By selecting
the femoral component that best accommodates an individual
patient's anatomy, the surgeon may assemble a prosthesis that more
closely approximates the natural anatomy of the patient.
In addition to the final, implanted components of a modular
prosthesis system, a modular prosthesis system may also include
provisional components which replicate the size and shape of the
final, implanted components of the modular prosthesis system. The
use of provisional components provides the surgeon with the ability
to test the ultimate configuration of the prosthesis prior to the
implantation of the final components. By trialing, i.e., testing,
the surgeon is able to determine whether the fit, alignment, and
range of motion provided by the final prosthesis will approximate
the patient's natural anatomy. Additionally, as many implants
achieve some measure of press fit with the resected bone, it is
important that the provisional components maintain similar
stiffness to the implant so that implant fit to bone can be checked
prior to implantation. To ensure that the provisional components
accurately replicate the function of the final, implanted
components, the provisional components are dimensionally equivalent
to the implanted components and are frequently manufactured from
the same material.
SUMMARY
The present invention relates to a provisional prosthetic system
and the surgical methods for utilizing the same. In one embodiment,
the provisional prosthetic system replicates the characteristics of
corresponding, nonprovisional femoral prostheses. In this
embodiment, the provisional prosthetic system includes a frame
component and a shell component. The frame component of the
provisional prosthetic system may be configured to be attached
directly to a resected femur. In one exemplary embodiment, the
frame component is impacted onto the resected femur to firmly seat
therewith. Once the frame component is secured to the resected
femur, the shell component of the provisional prosthetic system may
be positioned on and secured to the frame component. In one
exemplary embodiment, the frame component is made from a metallic
material. This allows for the frame component to maintain the
rigidity necessary to facilitate proper trialing. In another
exemplary embodiment, the shell component is a plastic. In yet
another exemplary embodiment, the shell component is fabricated by
injection molding.
To ensure that a provisional and, ultimately, a nonprovisional that
has the characteristics most suited for an individual patient are
selected, the provisional prosthetic system may include a plurality
of shell components having different characteristics, e.g.,
different sizes, orientations, and/or designs that correspond to
available nonprovisional prostheses. For example, if the prosthesis
includes three different nonprovisional implants having different
sizes, three provisional implants would be included in the
prosthesis system which correspond in size to the three
nonprovisional implants. Thus, a surgeon may attach a first shell
component to the frame component of the provisional prosthetic
system and trial, i.e., test, the same. If the surgeon is not
satisfied with the results of the current shell component, the
surgeon may remove the shell component from the frame component and
attach a different shell component having different
characteristics, until the best fit for an individual patient is
identified.
By utilizing the provisional prosthetic system of the present
invention, numerous benefits are realized. For example, by
utilizing the frame component and shell component design of the
present system, only a single frame component is attached to the
resected femur. Thus, the need to impact and remove various
provisional components from the resected bone is eliminated and
wear of the natural bone stock during the trialing of the
provisional components is lessened. Additionally, by eliminating
the need to manufacture the shell components of the provisional
prosthetic system from a metallic material, the weight of the full
complement of provisional components is substantially lessened.
This decreases the burden on operating room personnel and hospital
staff to stock, inventory, clean, and transport the full complement
of provisional components. Moreover, by manufacturing the shell
components of the present provisional system from plastic, for
example, the cost of producing the same is decreased.
Further, because a plurality of different shell components may be
attached to a single frame component, the total number of
provisional components in any given provisional system may be
decreased. For example, in an implant system having femoral
components for standard size, plus size, and minus size for each of
the left knee and the right knee, a single frame component may be
designed to accept all six configurations of the corresponding
shell components. Thus, a single frame can be combined with the
differing shell components to form provisional components that
accurately replicate the characteristics of the six corresponding
nonprovisional implants.
By providing a full complement of provisional components having a
mass and volume substantially less than that of a complement of
standard provisional components, a hospital may be more likely to
stock the entire system. Additionally, a surgeon may request the
entire complement of components in the operating room and thus the
surgeon may be able to achieve better extension and flexion gap
balancing, without the need to perform additional bone cuts or to
extensively test the flexion and extension gaps.
In one form thereof, the present invention provides a modular
provisional system, including a frame component configured to be
secured to the distal end of a femur; and a shell component
configured to be releaseably secured to the frame component, the
frame component and the shell component cooperating to form a
provisional implant which replicates the characteristics of at
least one nonprovisional component of a prosthesis system.
In another form thereof, the present invention provides a modular
provisional system, including a frame component having first
engagement structure, the frame component configured for securement
to the distal end of a femur; and a shell component having a frame
contacting surface and an articulation surface, at least a portion
of the frame contacting surface configured to engage the first
engagement structure of the frame component to secure the shell to
the frame, the articulation surface of the shell component shaped
to replicate natural femoral condyles, wherein the frame component
and the shell component cooperate to replicate a characteristic of
at least one nonprovisional component of a prosthesis system.
In another form, thereof the present invention provides a method of
trialing a femoral implant including the steps of attaching a frame
component to the distal end of a femur; attaching a shell component
having an articulation surface to the frame component, wherein the
frame component and the shell component cooperate to form a first
provisional implant; trialing the first provisional implant formed
by the frame component and the shell component.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this
invention, and the manner of attaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of an embodiment of the
invention taken in conjunction with the accompanying drawings,
wherein:
FIG. 1 is an exploded perspective view of one embodiment of the
provisional prosthetic system and depicting a resected femur;
FIG. 2 is another perspective view of the embodiment of FIG. 1,
taken from a posterior aspect;
FIG. 3 is another perspective view of the embodiment of FIG. 1
taken from a medial aspect;
FIG. 4 is an exploded perspective view of the provisional
prosthetic system according to another exemplary embodiment;
and
FIG. 5 is an assembled, perspective view of the provisional
prosthetic system of FIG. 4;
FIG. 6 is a partial assembled view of the provisional prosthetic
system of FIG. 1; and
FIG. 7 is an assembled view of the provisional prosthetic system of
FIG. 1.
Corresponding reference characters indicate corresponding parts
throughout the several views. The exemplifications set out herein
illustrates preferred embodiments of the invention and such
exemplifications are not to be construed as limiting the scope of
the invention any manner.
DETAILED DESCRIPTION
As shown in FIGS. 1-3, femoral provisional 10 includes frame
component 12 and shell component 14. Shell component 14 may be
attached to frame component 12, as shown in FIG. 7, to form
assembled femoral provisional 10, as described in detail below.
Referring to FIGS. 1-3, frame component 12 of femoral provisional
10 is configured for direct attachment to femur 16. As shown in
FIG. 1, femur 16 includes resected distal end 18 having apertures
20 and cutout 22 formed therein. Resected distal end 18 of femur 16
is fully resected, i.e., all of the cuts necessary for implantation
of a final, nonprovisional femoral component have been made. In
another exemplary embodiment, resected distal end 18 may include
only a portion of the cuts necessary to facilitate implantation of
the final, nonprovisional femur component. In this embodiment,
femoral provisional 10 may be utilized to facilitate a surgeon's
determination of the location for making the remaining cuts to
femur 16.
In one exemplary embodiment, frame component 12 is formed from a
metallic material, e.g., formed from a metal, a metal alloy, or a
material having properties that are substantially similar to a
metal or metal alloy. This provides frame component 12 with the
necessary rigidity to represent the rigidity of the corresponding
nonprovisional component on the resected bone and retain shell
component 14 in the proper position during trialing. Frame
component 12 of femoral provisional 10 includes bone contacting
surface 24 and posts 26, best seen in FIG. 2. Bone contacting
surface 24 of frame component 12 is shaped to mate with resected
distal end 18 of femur 16 and posts 26 are sized to be received
within apertures 20. Apertures 20 of femur 16 may be formed by
drilling, reaming, or any other known technique. Apertures 20 are
sized slightly larger than posts 26, but are close enough in size
to posts 26 that frame component 12 may be impacted to be properly
seated on distal end 18 of femur 16. While frame component 12 is
described and depicted herein as including posts 26, posts 26 are
not necessary to the function of frame component 12 and further
embodiments are envisioned in which posts 26 are absent.
Frame component 12 further includes shell contacting surface 27
having condylar bases 28, 30 connected by anterior bridge portion
32 and posterior bridge portion 34 (FIG. 3). In one exemplary
embodiment, posterior bridge portion 34 replicates the cam of a
Posterior Stabilized femoral implant. In another exemplary
embodiment configured for a Posterior Cruciate Ligament Retaining
femoral prosthesis, posterior bridge portion 34 is absent.
Additionally, ribs 36, 38 extend from shell contacting surface 27
of frame component 12 to add rigidity and facilitate retention and
alignment of shell component 14 upon frame component 12, as
discussed in detail below.
Referring to shell component 14, shell component 14 includes
posterior overhang 42, anterior overhang 43 (FIG. 2), and frame
contacting surface 40 forming condylar recesses 44. Condylar
recesses 44 are separated from overhangs 42, 43 by tapered leads
46, 47, respectively, which facilitate attachment of shell
component 14 to frame component 12. In one exemplary embodiment,
shell component 14 is formed from a plastic. For example, shell
component 14 may be formed from an injection molded polymer. By
forming shell component 14 from a plastic or other polymer, the
weight of shell component 14 and, correspondingly, femoral
provisional 10 is significantly reduced. Thus, a full complement of
provisional components made in accordance with the present
invention is significantly lighter than a full complement of
standard provisional components, lessening the burden on operating
room personnel and hospital staff who must transport the same.
Shell component 14 also includes articulating surface 48 having
condylar portions 50, 52 connected by anterior portion 54.
Referring to FIG. 2, shell component 14 further includes grooves
56, 58 extending through frame contacting surface 40 and overhang
43. Grooves 56, 58 are configured to receive and retain ribs 36, 38
of frame component 12, respectively, therein. Additionally, both
grooves 56, 58 include an indentation (not shown) configured to
matingly engage ribs 36, 38, respectively. Thus, receipt of ribs
36, 38 within the indentations of grooves 56, 58 provide for
retention of anterior portion 54 of shell component 14 upon
anterior bridge portion 32 of frame component 12. In one exemplary
embodiment, the engagement of ribs 36, 38 with grooves 56, 58 forms
a snap-fit connection. Moreover, ribs 36, 38 and grooves 56, 58
facilitate the alignment and seating of shell component 14 with
frame component 12 prior to attachment.
Referring to FIGS. 1-3, condylar recesses 44 (FIGS. 1 and 2) of
shell component 14 are configured to receive portions of condyle
bases 28, 30 of frame component 12 therein. Specifically, condylar
recesses 44 and tapered lead 46 are configured to engage posterior
portions 60, 62 and tapered edge 64 (FIG. 2), respectively. Thus,
posterior portions 60, 62 and condylar bases 28, 30 of frame
component 12 are in posterior mating engagement with condylar
recesses 44 and tapered lead 46 of shell component 14. In one
exemplary embodiment, the interaction of condylar recesses 44,
tapered lead 46, posterior portions 60,62 and tapered edge 64 forms
a snap-fit connection. To remove shell component 14 from frame
component 12, a surgeon simply lifts up on anterior portion 54 of
shell component 14, for example, to release the snap-fit
connection. Shell component 14 may then be replaced by another
shell component 14 having different characteristics.
To assemble femoral provisional 10 upon femur 16, femur 16 is
initially resected, as described above, to form resected distal end
18. Apertures 20 are then formed in resected distal end 18 of femur
16 and sized to receive post 26 of frame component 12 therein. In
one exemplary embodiment, frame component 12 is selected from a
plurality of frame components having different characteristics.
With post 26 aligned with apertures 20, frame component 12 is
impacted onto resected distal end 18 of femur 16 until bone
contacting surface 24 is in mating engagement with resected distal
end 18, as shown in FIG. 6. Referring to FIGS. 6 and 7, once frame
component 12 is securely seated on femur 16, one of a plurality of
shell components 14 having characteristics which a surgeon believes
would best accommodate a patient's natural anatomy is aligned with
and secured to frame component 12, as described in detail above.
Alternatively, one of a plurality of shell components 14 may be
secured to frame component 12 prior to seating frame component 12
on femur 16. Thus, once frame and shell components, 12, 14 are
secured together, the assembly is impacted on femur 16 as described
above. With shell component 14 secured to frame component 12 and,
correspondingly, femur 16, a surgeon may perform trialing of
femoral provisional 10.
In the event the surgeon determines that femoral provisional 10
satisfactorily replicates the patient's natural anatomical
movement, shell component 14 may be removed from frame component 12
and frame component 12 removed from femur 16. A nonprovisional
femoral component having characteristics which correspond to
femoral provisional 10 is then implanted using standard surgical
techniques.
In the event a surgeon determines femoral provisional 10 does not
satisfactorily replicate a patient's natural anatomical movement,
shell component 14 may be removed from frame component 12, which
provides the sole securement of shell component 14 to femur 16 as
described in detail above, and a different shell component 14
having different characteristics may be attached to the same frame
component 12. By using a single frame component 12 capable of
attachment to multiple shell components 14, the need to impact and
remove various frame components 12 is eliminated. Thus, wear of
resected distal end 18 of femur 16 is lessened. Additionally, by
providing for attachment of multiple shell components 14 to a
single frame component 12, the total number of components is
lessened. The surgeon may then trial the new femoral provisional
10. Once a surgeon has identified the one of a plurality of shell
components 14 that would satisfactorily replicate the patient's
natural anatomical movement, femoral provisional 10 may be removed
from femur 16, as described in detail above, and the corresponding
nonprovisional femoral component implanted.
Referring to FIG. 4, another exemplary embodiment of frame
component 12 and shell component 14 are depicted as frame component
70 and shell component 72. Frame component 70 and shell component
72 include several components which are identical or substantially
identical to components of frame component 12 and shell component
14, respectively, and corresponding reference numerals are used to
identify identical or substantially identical components
therebetween. As shown in FIG. 4, frame component 70 includes
openings 74 formed in condylar bases 28, 30 and anterior bridge
portion 32. Similarly, shell component 72 includes projections 76
formed on condylar portions 50, 52 and anterior portion 54.
Projections 76 are sized and configured to be received with
openings 74 of frame component 70. Thus, as shown in FIG. 5,
receipt of projections 76 of shell component 72 within openings 74
of frame component 70 provides a snap-fit connection between frame
component 70 and shell component 72.
To separate frame component 70 and shell component 72, a surgeon
may exert a force on anterior portion 54 of shell component 72, in
a direction away from frame component 70, to disengage one of
projections 76 from one of openings 74. Once shell component 72 is
removed from frame component 70, a different shell component 72
having different characteristics may be attached to frame component
70 in a similar manner. In another exemplary embodiment, frame
component 70 may include a projecting rib and shell component 72 a
corresponding groove to facilitate alignment of frame component 70
and shell component 72 to facilitate proper seating and retention
of shell component 72 on frame component 70.
While this invention has been described as having a preferred
design, the present invention can be further modified within the
spirit and scope of this disclosure. This application is therefore
intended to cover any variations, uses, or adaptations of the
invention using its general principles. Further, this application
is intended to cover such departures from the present disclosure as
come within known or customary practice in the art to which this
invention pertains and which fall within the limits of the appended
claims.
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